Ribbon guide for typewriter ribbon cartridge

ABSTRACT

A ribbon guide or carrier arm for a typewriter ribbon cartridge is disclosed. The carrier arm which is pivotally connectable to the cartridge housing to laterally extend therefrom, has means for guiding a ribbon from the housing to a print point and back to the housing. An aperture is provided adjacent the end of the arm for exposing a portion of the ribbon to a type element at the print point. A retaining finger is provided adjacent the aperture to retain the ribbon for uniform smudge free typing. A cap on the end of the arm cooperates with the retaining finger in retaining the ribbon.

United States Patent [191 Stewart RIBBON GUIDE FOR TYPEWRITER RIBBONCARTRIDGE [75] inventor: Durwood Stewart, Groton, NY.

[73] Assignee: SCM Corporation, Cortland, NY.

[22] Filed: May 3, 1972 [21] Appl. No.: 249,953

[52] US. Cl. 197/151, 197/170 [51] Int. Cl B4lj 33/14 [58] Field ofSearch 197/151, 153 R, 153 A, 197/157, 158,159, 170,162, 168; 101/336[56] References Cited UNITED STATES PATENTS 3,643,777 2/1972 Anderson eta1. 197/151 2,869,705 1/1959 Gates 197/151 809,378 l/1906 Kay 197/170 UX2,464,042 3/1949 Inskeep 101/336 2,883,029 4/1959 Gray 197/162 3,590,2216/1971 Malkowski 197/168 UX [4 1 Mar. 26, 1974 3,643,778 2/1972 Anderson197/151 3,643,779 2/1972 Anderson et al. 197/151 623,502 4/1899 DelaMar197/151 Primary EraminerErnest T. Wright, Jr. Attorney, Agent, orFirm-Milton Wolson; Harvey Zeller; John Taylor [5 7 ABSTRACT armcooperates with the retaining finger in retaining the ribbon.

11 Claims, 4 Drawing Figures RIBBON GUIDE CARTRIDGE BACKGROUND OF THEINVENTION The present invention relates to ribbon guide or carrier armsfor typewriter ribbon cartridges of the type having a housing and acarrier arm laterally extending therefrom to guide a ribbon from thehousing to a print point in the typewriter and thereafter return theribbon to the housing. More specifically, the present invention relatesto car-rier arms for use in ribbon cartridges of the type disclosed inUS. Pat. No. 3,643,777 entitled TYPEWRITER RIBBON CARTRIDGE and US. Pat.No. 3,643,779 entitled RIBBON MECHANISM FOR CARTRIDGE SUPPORTED RIBBONSboth granted Feb. 22, 1972 and US. Pat. application Ser. No. 150,946filed June 9, 1971 entitled TYPEWRITER RIBBON CARTRIDGE all assigned tothe assignee of the instant application.

Ribbon cartridges and other devices for typewriters or like printingmachines have been provided to assist in the installation of ribbonsinto such machines and to minimize the soiling of fingers during suchprocess. In addition, such cartridges and devices have been foundhelpful in increasing the lifespan of the ribbons and the uniformity ofprinting by shielding the ribbon from exposure to environmentalelements. In this connection, a recent advance in the art of typewriterribbon cartridges has been the development of typewriter ribboncartridges of the type disclosed in the above referred to patentapplications assigned to the present assignee. These cartridges employ ahousing for a supply of ribbon and a ribbon guide carrier arm laterallyextending from the housing for guiding the ribbon from the housing to aprint point within the typewriter and back to the housing. Thesecartridges are insertable in the typewriter to a position wherethe armis engaged by a lift mechanism in the typewriter. Thus, there is no needfor threading of the ribbon nor other manipulations which are timeconsuming and cause soiling of the fingers.

Furthermore, the cartridges are removable by sliding thecartridge fromthe typewriter thus enabling easy replacement or variation in color ortype of ribbon, e.g. carbon ribbon or fabric'ribbon. A

In cartridges of the above type, the guide or carrier arm'must define apath for the flow of ribbon which offers little resistance to the flowand which insures against snagging. The guide must also minimize saggingas well as transverse bulging of the ribbon which could cause the ribbongoing to the print point and that coming from it to rub against eachother or parts of the typewriter or record receiving medium and thusdisturb the flow of ribbon and cause smudging or unreliability.

It is therefore an object of the instant invention to achieve a ribbonguide or carrier arm of the type laterally extending from, a typewriterribbon cartridge wherein the carrier arm provides means for guiding theribbon with minimum possibility of snagging, sagging or bulging.

SUMMARY OF THE INVENTION The present invention consists of a ribbonguide or carrier arm for a typewriter ribbon cartridge of the typehaving a housing for a supply of ribbon and a ribbon guide or carrierarm laterally extending therefrom to guide the ribbon from the housingto the print point and back to the housing. The carrier arm which ispivotally connectable to the housing is provided with an elongatedsection having shielded channels formed therein for guiding the ribbon.Adjacent the elongated section is an aperture for threading the ribbonthrough the carrier arm and finger retaining means preventing the ribbonfrom sagging and bulging in the vicinity of a second subsequent apertureto be positioned adjacent the print point in the typewriter for exposingthe ribbon for printing. Following the print point aperture is a V-shaped section for reversing direction of flow of the ribbon. Theentrance to the V-shaped section has channel means to permit entry ofthe ribbon and a hollow V- shaped cap is provided which assists inpreventing said sagging and bulging.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a partial perspective view ofa typewriter having a cartridge thereon employing the ribbon guide orcarrier arm of the instant invention;

FIG. 2 is a rear perspective view of the ribbon guide or carrier armshowing its pivotal connection to the cartridge;

FIG. 3 is a front perspective view of the ribbon guide or carrier armwith the ribbon shields removed showing how the ribbon is guided alongand threaded through the carrier arm; and

FIG. 4 is an exploded perspective view of the ribbon guide or carrierarm of the instantinvention.

DETAILED DESCRIPTION OF THE INVENTION Having generally described theinstant invention a more detailed description will now be given of apreferred embodiment thereof with specific reference to FIGS. 14.

Referring initially to FIG. 1, the ribbon guide or carrier arm 10 isshown laterally extending from a housing 11 of a typewriter ribboncartridge 12 of the type described in the above referred to patentapplications assigned to the present assignee. The cartridge 12 isinsertable into the typewriter 14 to a point where a stud 16 on thecarrier arm 10 engages a lever 18 of a lift mechanism 20. The carrierarm 10 has a window or aperture 22 therein which is aligned behindtypebar guide 24 to expose a portion of the ribbon 26 to a typingelement 26a. During a typing operation the lift mechanism 20 liftscarrier arm 10 raising ribbon 26 to a point indicated generally at 27adjacent the print point of the typewriter 14 where the ribbon 26 isstruck by a typing element 26a to transfer an inked character to thepaper or other record medium.

Referring next to FIGS. 2-4, the carrier arm 10 is pivotally mounted onthe cartridge 12 by a stud 28 which rests on fulcrum 30. A spring 32 hasone end thereof extending through aperture 34 in the fulcrum 30 toremain secure to the cartridge 12 and its opposite end engages thehook-like tab 36 on the carrier arm 10 to retain the carrier arm 10 inposition biased counterclockwise in the view of FIG. 3 to a restposition which maintains the carrier arm 10 at the correct orientationto engage lever 18 of the lift mechanism 20 during insertion of thecartridge 12 in the typewriter 14.

The carrier arm 10 has an elongated body 38 having flanges 40 and 42extending therealong. Situated between flanges 40 and 42 parallelthereto is partition 44. Partition 44 is shorter than the portions offlanges 40 and 42 directly opposite it. Flanges 40 and 42 and partition44 thus provide channels 44a and 44b for the flow of ribbon 26.

Aperture 46 is provided permitting ribbon 26 to pass to the rear side ofcarrier arm 10. The rear side of carrier arm is provided with flanges 48and 50 and partition 52 between these flanges 48 and 50 to form proximalchannels 49 and 51. In addition, retaining finger 54 is providedintegral with partition 52 having a thickness partially extending into arecess or window 53. Flanges 48 and 50, partition 52 and retainingfinger 54 guide the ribbon 26 to and from print point aperture 22.

The end of carrier arm 10 has a V-shaped end or section 54a and has ateat-like projection 55 on the vertex thereof. At the mouth of theV-shaped section 540 of the carrier arm 10 is a flange, step, orshoulder 56 which extends around the carrier arm 10 and has distalchannels therethrough at 56a and 56b separated by a partition 57. Thechannels 56a and 56b define a path for the ribbon 26 which enters theV-shaped section 54a of the carrier arm 10, goes around the legs of theV-shaped section 54a and leaves the V-shaped section 5411.

A first shield in the form ofa cover plate 58 (see FIG. 4) is providedfor shielding the ribbon 26 along the carrier arm 10 as well asretaining the ribbon 26 in the channels 44a and 44b. Cover plate 58 hasan aperture therein at 60 and partition 44 has a hook-like finger 62thereon. In addition, a shoulder or abutment 64 is provided on thecarrier arm 10 facing the opening of the hook-like finger 62. Thus, thecover plate 58 is secured to the carrier arm 10 by placing it over thehook-like finger 62 to have the latter extend through the aperture 60and sliding the cover plate 58 to the right until its end 59 fallsbehind and abuts abutment 64 which prevents its accidental removal.

A second shield is provided in the form of a hollow V-shaped cap 66which is mounted upon the step or shoulder 56 to permit the entry anddeparture of the ribbon 26 to and from the Y-Shaped section 54a of thecarrier arm 10 without adding to the friction on the ribbon 26. Anaperture 67 is provided in cap 66 to receive teat-like projection 55 toalign the cap 66 on the carrier arm 10 and prevent ribbon 26 fromsnagging or riding over the end of the carrier arm 10.

Finger 54 and cap 66 cooperate to retain the upper portion of ribbon 26adjacent the plane of the carrier arm 10 against movement transverse orperpendicular to that plane as well as against movement transverse tothe flow of ribbon 26. Thus, the ribbon 26 is prevented from sagging orbulging in the vicinity of the print point where such occurence wouldcause smudging as well as undesirable rubbing of the ribbon 26 againstthe typewriter 14 which could interfere with the line indicator.

In the preferred embodiment of the instant invention all of the parts ofthe carrier arm 10 are plastic with the exception of the V-shaped cap 66which is preferrably metal so that it may be pinched onto the end 540 ofthe carrier arm 10. In addition, the cover plate 58 may be madetransparent if desired to make the ribbon 26 visible whereby indiciasuch as indicating of the end of the ribbon 26 may be seen on the ribbon26. While the instant invention has been described with respect to apreferred embodiment thereof, many modifications thereof will now becomeapparent to those of ordinary skill in the art. Thus, it is desired thatthe scope of the invention not be limited by the foregoing illustrativedescription but rather by the appended claims.

I claim:

1. An improved cartridge for a ribbon for a typewriter having at leastone typing element, the cartridge having a housing and an arm forguiding a loop of the ribbon having upper and lower limbs from thehousing to the end of the arm, the arm having a first window forexposing the upper limb of ribbon to the typing element, wherein theimprovement comprises the arm having a recess in a rear surface of saidarm near the housing side of the first window and a finger projectingupward from the lower portion of the recess and positioned at leastpartially in the recess to guide the upper limb of ribbon between thefinger and the recess so that the upper limb of ribbon will be tautacross the first window even during and immediately after impacts of thetyping element.

2. The cartridge of claim 1 in which the finger is formed integral withthe arm from a plastic.

3. The cartridge of claim 1 in which the recess is a second window.

4. The cartridge of claim 1 in which the arm has a first proximalchannel at least as wide as the width of the ribbon in said rear surfacein communication with the housing side of the first window, the recessis in a portion of the first proximal channel and substantially spansthe first proximal channel, the finger projects upward from the lowerportion of the first proximal channel, and the upper portion of thefirst proximal channel overhangs at least a portion of the top of thefinger so that the upper limb of ribbon will be trapped in the firstproximal channel between the finger and the recess.

5. The cartridge of claim 4 in which the arm has a V- shaped end with afirst distal channel at least as wide as the width of the ribbon in saidrear surface in communication with the V-shaped end side of the firstwindow and substantially in line with the first proximal channel to helpsupport the upper limb of ribbon across the first window.

6. The cartridge of claim 5 in which the arm has a hollow V-shaped capon said V-shaped end to trap the upper limb of ribbon in the firstdistal channel.

7. The cartridge of claim 4 in which the arm has a second proximalchannel at least as wide as the width of the ribbon in said rear surfacein communication with the housing side of the first window below thefirst proximal channel to guide the lower limb of ribbon.

8. The cartridge of claim 7 in which the arm has a V- shaped end withfirst and second distal channels each at least as wide as the width ofthe ribbon in said rear surface in communication with the V-shaped endside of the first window and substantially in line with the first andsecond proximal channels respectively to help support the upper limb ofribbon across the first window and to guide the lower limb of ribbon.

9. The cartridge of claim 8 in which the arm has a hollow V-shaped 'capon said V-shaped end to trap the upper and lower limbs of ribbon in thefirst and second distal channels respectively.

10. The cartridge of claim 9 in which, except across the first andsecond distal channels, the V-shaped end of the arm has a flange aroundthe mouth of the V to guide the ribbon across the front face of theV-shaped end and to provide a mounting surface for the hollow V-shapedcap.

11. The cartridge of claim 10 in which the V-shaped end of the arm has aprojection on the point of the V and the hollow V-shaped cap has anaperture in the point of the V for the projection to help position thecap on the end of the arm and to prevent the ribbon from riding over theend of the arm.

1 i t i i

1. An improved cartridge for a ribbon for a typewriter having at leastone typing element, the cartridge having a housing and an arm forguiding a loop of the ribbon having upper and lower limbs from thehousing to the end of the arm, the arm having a first window forexposing the upper limb of ribbon to the typing element, wherein theimprovement comprises the arm having a recess in a rear surface of saidarm near thE housing side of the first window and a finger projectingupward from the lower portion of the recess and positioned at leastpartially in the recess to guide the upper limb of ribbon between thefinger and the recess so that the upper limb of ribbon will be tautacross the first window even during and immediately after impacts of thetyping element.
 2. The cartridge of claim 1 in which the finger isformed integral with the arm from a plastic.
 3. The cartridge of claim 1in which the recess is a second window.
 4. The cartridge of claim 1 inwhich the arm has a first proximal channel at least as wide as the widthof the ribbon in said rear surface in communication with the housingside of the first window, the recess is in a portion of the firstproximal channel and substantially spans the first proximal channel, thefinger projects upward from the lower portion of the first proximalchannel, and the upper portion of the first proximal channel overhangsat least a portion of the top of the finger so that the upper limb ofribbon will be trapped in the first proximal channel between the fingerand the recess.
 5. The cartridge of claim 4 in which the arm has aV-shaped end with a first distal channel at least as wide as the widthof the ribbon in said rear surface in communication with the V-shapedend side of the first window and substantially in line with the firstproximal channel to help support the upper limb of ribbon across thefirst window.
 6. The cartridge of claim 5 in which the arm has a hollowV-shaped cap on said V-shaped end to trap the upper limb of ribbon inthe first distal channel.
 7. The cartridge of claim 4 in which the armhas a second proximal channel at least as wide as the width of theribbon in said rear surface in communication with the housing side ofthe first window below the first proximal channel to guide the lowerlimb of ribbon.
 8. The cartridge of claim 7 in which the arm has aV-shaped end with first and second distal channels each at least as wideas the width of the ribbon in said rear surface in communication withthe V-shaped end side of the first window and substantially in line withthe first and second proximal channels respectively to help support theupper limb of ribbon across the first window and to guide the lower limbof ribbon.
 9. The cartridge of claim 8 in which the arm has a hollowV-shaped cap on said V-shaped end to trap the upper and lower limbs ofribbon in the first and second distal channels respectively.
 10. Thecartridge of claim 9 in which, except across the first and second distalchannels, the V-shaped end of the arm has a flange around the mouth ofthe V to guide the ribbon across the front face of the V-shaped end andto provide a mounting surface for the hollow V-shaped cap.
 11. Thecartridge of claim 10 in which the V-shaped end of the arm has aprojection on the point of the V and the hollow V-shaped cap has anaperture in the point of the V for the projection to help position thecap on the end of the arm and to prevent the ribbon from riding over theend of the arm.